Calculator



FIG. 1 is a top perspective view of a calculator showing our new design;

FIG. 2 is a top view thereof;

FIG. 3 is a right side view thereof, the left side view being the same;

FIG. 4 is a rear view thereof; and,

FIG. 5 is a front view thereof. 

The ornamental design for a calculator, as shown and described. 